1. Technical Field
The present invention relates to a load-sensing element for a balance, and in particular to a load-sensing element for a balance embodied by a beam that receives a load on one end. The balance has a horizontal recess with substantially reduced, identical cross sections of material on the top and bottom of the recess which form bending points, in such a manner as to make two guide bars of a parallel guide between the bending points, and in which a measurement signal is derived by wire strain gauges on the bending points.
2. Prior Art
A load-sensing element of this type is known from European Patent Document 0 227 850. It is disadvantageous that the bending points of one guide bar are unequally strained, because the bending moment of the entire beam is superimposed on the bending moments of the individual guide bars. To compensate for this, it is known to embody the material cross sections at the bending points differently (European Patent Document 0 207 240). It is also known to improve the linearity of such a load-sensing element by the special disposition of a connecting rod between one guide bar and a measurement cell (German Published, Unexamined Patent Application DE-OS 32 39 002).
A disadvantage of the known load-sensing elements is that when there is a large new load, the resultant measurement signal varies sharply if the engagement point of the load longitudinally of the beam changes even slightly--in a range of as little as 1/10 of a millimeter--as can happen from wear, for example.